import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main2 {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int l = in.nextInt();
        int r = in.nextInt();
        int[] a = new int[n];
        for(int i = 0; i < n; i++) {
            a[i] = in.nextInt();
        }

        int cnt = 0;
        for(int i = 0; i < n; i++) {
            for(int j = i + 1; j < n; j++) {
                if(Math.abs(a[i] - a[j]) <= r && Math.abs(a[i] - a[j]) >= l) {
                    cnt++;
                }
            }
        }
        System.out.println(cnt);
    }
}